Homework Help:
Angular velocity of bicycle wheel

1. The problem statement, all variables and given/known data
A bicycle rider is moving with a velocity of 13.0 m/s. What is the angular velocity of his wheels if they have a diameter of 0.660m? Assume the wheels are rolling without slipping.

a) 39.4 m/s
b) 19.7 m/s
c) 39.4 s-1
d) 4.29 s-1
e) none of the above

2. Relevant equations
v = ω r

3. The attempt at a solution
ω = v/r
ω = (13m/s) / (0.330m) = 39.4 s-1
This problem was given on a test, I put "c" and got it wrong. It seems very straightforward and I'm not sure where I went wrong. Is there a mistake in my work? Im thinking it was most likely a mistake with the grading machine but I just wanted someone to confirm before I talked to the teacher. Thanks.

Yes, your answer is definitely correct. Note that you almost don't need the question. Just looking at the choice of answers, and assuming each wrong answer corresponds to a single likely error, (c) stands out as the common theme.